For most of the residents of Tachikawa city, life seems to be perfectly normal. That's how it seems, but the truth, known only by a tiny select handful, is that this is a city at war. Every day, as the citizens go about their business, they are under attack by alien criminals and mysterious organizations seeking to conquer, enslave and destroy. But to combat these threats, a covert council has secretly selected certain individuals to serve as protectors.

Wearing special suits that amplify latent powers hitherto unsuspected, they blend into the crowds and shadows, waiting until the call is given to fight again. They could be anyone: your neighbor, your best friend's mom, even high school students like Sugune Tachibana and recent college grad Joe Hibiki. And needless to say, schoolgirl artist Hajime Ichinose is probably the last person anyone would ever suspect of being a soldier entrusted with defending mankind. But she is, even if as the latest recruit she still has an awful lot of learning to do. Hiding like ninjas, powered by super-science, they are humanity's first and greatest line of defense.